Re: Does converting an indexed varchar to text rewrite its index? Docs say so, tests say no.

You wrote:

> Well it did not rebuilt the index("t1_name_idx") you created on name.

OK, so then the docs *are* wrong? They say that:

> any indexes on the affected columns must still be rebuilt.

But that doesn't happen? Sorry to be persistent. I'm just a bit confused
here.

On Thu, Jan 23, 2020 at 11:28 AM Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com>
wrote:

> On 1/23/20 11:17 AM, Mike Lissner wrote:
> > Thanks Adrian. Is there a reason that the index rebuild is nearly
> > instant during the ALTER command as opposed to when you build it from
> > scratch?
>
> Well it did not rebuilt the index("t1_name_idx") you created on name.
>
> >
> > Does it have to do with why this is called a "toast" index?
>
> Certain data types(those that have varlena) can have portions of their
> data stored in an auxiliary table in a compressed(or not) form. For all
> the details see:
>
> https://www.postgresql.org/docs/12/storage-toast.html
>
> The index is the one on this auxiliary table.
>
> >
> > DEBUG: building index "pg_toast_37609_index" on table "pg_toast_37609"
> >
> > Thanks for the feedback. I really appreciate it and it's super
> > interesting to learn about.
> >
> > Mike
> >
>
>
>
> --
> Adrian Klaver
> adrian(dot)klaver(at)aklaver(dot)com
>